Register regulator control



F. H. GULLIKSEN I 2,195,006 REGISTER REGULATOR CONTROL March 26, 1940.

Filed April 14, 193B 2 Sheets-Sheet 1 INVENTOR F2727? H Gui/itsen.

BY M 8.

ATTORNEY 2 Sheets-Sheet 2 March 26, 1940. F. H. GULLIKSEN REGISTERREGULATOR CONTROL Filed April 14, 1938 F7777? HGzM/i/ben.

' ATTORNEY Patented Mar. 26, 1940,

PATENT OFFICE REGISTER REGULATOR CONTROL Finn H. Gulliksen, Wilkinsburg,

Pa., asslgnor to Westinghouse Electric & Manufacturing Company, EastPittsburgh, Pa.,

Pennsylvania a corporation of Application April 14, 1938, Serial No.201,950

16 Claims.

This invention relates to electrical control systems for apparatusoperating on material.

, More specifically, this invention relates to electrical controlsystems involving thermionic means and light-sensitive means forcontrolling the relative positions and relative speeds of certain partsof a machine operating on a web of material.

In the art of paper cutting, winding, printing, or other manufacturingprocesses, such as the making of bags, the operation of the paper or webof material, when moving from a supply reel past certain rolls to thecutter, or to other parts of the machine, nearly always involvesslippage, whereby the paper becomes shifted relative to the cutter orother machine element. Even when there be no slippage, the hygroscopiccharacteristics of paper, or temperature, or both, will cause a changein its dimensions, and also its surface characteristics, with changes ofrelative humidity and/or changes in temperature, with the result thatcertain machine elements will not register with the paper in the desiredmanner. Slippage and the moisture effect may, of course, occursimultaneously.

One object of my invention is to provide for properly registeringcertain regions of a material being operated upon by a machine withcertain elements of the machine.

It is another object of this invention to con-- trol the operation ofapparatus operating on a web so that the required operation on the webwill take place at the right point, regaudless of slippage of the web,or changes of dimensions or the surface characteristics thereof.

It is also an object of my invention to provide means for correcting inone continuous operation each departure from registry of a material andcertain elements of a machine operating on it.

Another object of this invention is to control the relative speeds of acutter and the feeding means of amachine, operating on a web, by meansof photo-electric control means.

A further object of this invention is to control the position of theweb, in a machine operating on a web, by photo-electric control means.

It is also an object of my invention to provide electronic selectivecontrol means for controlling the direction of operation of a motor orother electrical device in response to variations in position of a markon a material operated upon by a machine.

Another object of my invention is to provide electronic timing means forcontrolling the operation of a motor.

Another object of this invention is to control the relative speeds ofcertain parts of a machine operating on a web and the relative positionsof these parts by the cooperative action of photoelectric and thermionicmeans.

A board object of my invention is to provide photo-electric controlmeans, unaffected by changes in color of the material being operatedupon by a machine or by changes in appearance or by changes in thecharacter or the condition of the material, to control the machine sothat certain elements of the machine are caused to register with theindicia which may be either on or in the material.

A still further broad object of my invention is to provide acompensatingcontrol system, including photo-electric means for compensating forchanges in the color and depth of color of the web, shade of the web andthe character, shade and color of the indicia which may be either on orin the web, to register certain elements of a machine operating on a webwith selected regions of the web. I

The novel features that I consider characteristic of my invention areset forth with particularity in the appended claims. The inventionitself, however, both as to its organization and its method ofoperation, together with additional objects and advantages thereof,will'best be understood from the following description of specificembodiments, when read in connection with the accompanying drawings, inwhich:

Figure l is a diagrammatic representation of an electrical controlsystem embodying my invention; and,

Fig, 2 is a diagrammatic representation of a modification of myinvention.

Referring more particularly to Figure 1 of the drawings, an electricmotor ll, preferably an induction motor, is supplied with electricalenergy from buses l3 through line contactor IS. A cutter I! is coupledto the motor ll through a reduction gear Ill. The motor II is alsoutilized to drive a web feeding mechanism 2| which feeds a strip of webmaterial 23 having indicia 25 thereon, to the cutter H. The indlcia 25comprises spots or marks printed on or appearing in the web 23 andspacedat predetermined intervals. The operation of the web feeding mechanism2| takes place through a mechanical differential or localizer 21 havinga housing 29, a speed changer 3| and reduction gearing 33. The

localizer 21 may be adjusted by motor means such I as a motor 35 havinga pair of differentially wound field windings 31 and 39. The speedcontroller 3| may be adjusted by hand wheel 4|. It will readily beunderstood that a motor may be utilized to adjust the speed controller3| and a hand wheel may be utilized to adjust the localizer 21.

Associated with the apparatus for operating on the web 23 arelight-sensitive or radiation responsive scanners 43 and 45. Thelight-sensitive means or photo-electric scanner 43 comprises a pair ofphoto-electric devices 41 and 49 and a light source 5| disposed to bemounted for scanning the web material 23 and the indicia 25. The scannermeans 45 comprises a photo-electric device 53 actuated by thecooperative action of a light source 55 and a disc 51. The disc, havinga hole or slot 59, is disposed to be coupled to and actuated by thecutter I1.

The direction of operation of the motor 35 is controlled by two pairs ofelectric discharge devices BI and 63 which are in turn controlled by theelectronic timing means 65 and 61, respectively. The timing means 65comprises an electric discharge device 69, a capacitor 1| and anadjustable resistor 13. Similarly the timing means 61 comprises anelectric discharge device 15, a capacitor 11 and an adjustable resistor19.

The electric discharge devices 69 and 15 are controlled by thecooperative action of the scanner means 43 and 45 and a selectivecontrol means 8|. The selective control means 8| which may be a balancedbridge network, comprises resistors 83, 85, 81 and 89 and an electricdischarge device 9I, preferably of the high vacuum type, having acathode 93, an anode 95 and a control electrode 91. An additionalcontrol electrode 99 may be utilized, as shown, to obtain a higheramplification factor for the discharge device. The electric dischargedevice 9| is controlled by the scanner means 43.

The operation of the system, generally stated, embodies thesynchronizing of the indicia 25 on the web 23 with the slot 59 in thedisc 51 which rotates with the cutter I1. This synchronization thusprovides that the cutter will cut the web of material each time when theindicium or spot 25 with reference to which a given out is to be madehas a definite relation with reference to the cutter I1. When themovement of the spots 25 is synchronized with reference to the cutter,the photo-electric device 41, or 49, as the case may be, does notfunction simultaneously or substantially simultaneously with thephotoelectric device 53. If, however, the movement of the spots 25 isnot in proper relation with reference to the cutter I1, the impulsegiven either by the photo-electric device 41, or 49, occurssubstantially simultaneously with the impulse given by thephoto-electric device 53 thereby causing the operation of the timingmeans 65, or 61, which controls the operation of the pairs of dischargedevices 6| or 63, respectively, and thus the direction of rotation ofmotor 35.

Operation of the motor 35 causes a shift in the relative position of thecutter I1 and the web feeding mechanism 2| in one direction or theother, and operation of the hand wheel causes a selected change in thespeed difference between the cutter i1 and the web feeding mechanisms 2i As broadly hereinbefore indicated, when motor 35 is caused to operatethe change in speed relation between the cutter and the web feedingmechanism is to make the correction necessary to synchronize the spot onthe web and the knife of the cutter. The operation of motor 35 operatingon housing 29 of the differential mechanism 21 causes a shift in theposition between the cutter I1 and the web feeding mechanism 2I in sucha direction as to correct for the amount of asynchronous operationbetween the cutter blade and the spot on or in the web. The timing means65 and 61 may be so adjusted that the motor 35 will continue to operateuntil the correction necessary shall have been completed and no furthersynchronizing operation is necessary.

An important factor in any cutter control application is the mechanicalarrangement of the feeding roll, speed changing device, and thelocalizer equipment. In some cutting applications the slip of the paperis relatively small, in others substantially zero, and in still otherspractically constant, so that when the speed ratio between the cutterand the feed roll is properly adjusted by the hand wheel 4|, the entirecontrol can thereafter be obtained by means of the automatic adjustmentof the localizer or differential mechanism 21.

A better understanding of the invention may be had from a study of thesequence of operation involving a typical synchronizing operation forthe embodiment of my invention. In Fig. 1, reference characters MI andI03 represent a pair of conductors or bus bars. If the bus bars IN andI03 are assumed to be suitably energized. a number of energized circuitsare thereby established because transformers I05 and I01 are energizedwith the result that full-wave rectifiers I09, IIO, IlI, H3 and H5 areenergized to provide the necessary direct current potential for thetiming means, bridge networks, as well as the desirable bias for thecontrol electrodes or grids of the respective electric discharge devicesconstituting part of my system of control.

Ordinarily the photo-electric devices 41 and 49 of the photo-electricscanner 43 are positioned relative to each other so that they do notscan the same region at the same time. The preferable positioning issuch that the scanning takes place near the margin of the material inthe line of movement of the material so that each spot 25 is not scannedsimultaneously but successively by the photo-electric devices 41 and 49.

For a complete cycle operation of my system of control it must beassumed that the switch II 1 has been closed to energize the actuatingcoil 9 of the line contactor I5, thereby energizing the motor II fromthe conductors l3. Operation of the motor II drives the cutter I1 andthe disc 51 through the reduction gear I9. This motor also drives theweb feeding mechanism through the differential or localizer 21, thespeed changing device 3|, and the reduction gearing 33. The material isthus fed from a supply reel 621 and passes over the idling andtension-adjusting rollers I23 and I 25 to the feeding mechanism 21. Aswill be observed, any movement of a cam I21 will operate the springbiased levers I29 and HI in such a direction that the coneshapedtwo-part pulleys I33 and |35 will change the speed of the feedingmechanism 2| relative to the speed of the cutter I 1. The cam 121 isprovided with the hand wheel 4| for manually adjusting the relativespeed of the feeding mechanism 2| and the cutter I1.

As long as the housing 29 remains fixed, the relative position ofcertain parts of the cutter and the feeding mechanism remains fixed, andduring operation, the relative speeds of the cut tends from one side ofthe ter and the feeding mechanism remain constant.

Specific dimensions, or a given nature of the Indicia are not materialto my invention. 'It sui'llcient that some indicia be placed on the webor in the web at the points it is desired to have the web material cutor at some predetermined position with reference to the desired cut,

'so that the amount of light transmitted from the source of light to thephoto-electric device is periodically modified. It will, therefore, beunderstood that the color difierential between the indicia and the webmay be such that the iigzlcia', when entering or leaving the regionbescanned, will decrease in the current passing through the respectivephoto-electric devices.

If the apparatus is in normal operation, and' the adjustment of the webwith reference to the cutter, as wellas thespeed'ofthe cutter I1 withreference to the web feeding-device 2| has been properly eflected, eachspot 25 will arrive at a central position relative to the photo-electricdevices 41 and 49 when the slot 59 in the disc 51 reaches such aposition relative to the light source 55 that the, photo-electric device53 becomes activated, as long as the feeding mechanism and the cutterremain in synchronism. At these instances one spot will thus be betweenthe regions scanned by the photo-electric devices 41 and 49 and it maybe either. entirely outside of the region scanned 'or each end of thespot 25 may extend into a portion of the respective regions scanned insuch a manner that the photoelectric devices 41 and 49 will besubstantially equally affected.

The photo-electric devices 41 and 49 are connected in a bridge networkI31 comprising resistors I39, HI and I43 and energized by the rectifierI99. The bridge network I31 is connected between the control electrode91 and the cathode 93 of the discharge device a conventional gridresistor I44.

I45 is also connected between the control electrode 91 and the cathode99 to by-pass alter- 9I through nati'ng current ripples caused by linevoltage surges and static pick-up in the control electrode circuitleads. The potential between the control electrode 91 and the cathode 93is adjusted by moving an adjustable conductor I41 on resistor I43 untilthe current through the discharge device 9I is at an intermediate valueand the voltage across the resistor 83 is zero or substantial y zerowhen illumination from the light source 5| of substantially equalintensity is reflected from the web onto the photo-electric devices 41and 49. As hereinabove stated the discharge device 9| is part of thebridge network 8| which is energized by the rectifier 9. When variationsin the illumination or the color, finish and other characteristics ofthe web material affect both photo-electric devices 41 and 49 equal y,the current through the discharge device 9| and thus voltage across theresistor 83 remains unchanged. When the illumination on one of thephoto-electric devices 31 or 49 is modified relative to that of theother the current through the discharge device 9| is changed and avoltage is established across the resistor 93. The polarity of thisvoltage depends upon whether the current through the discharge device 9|has been increased above or decreased below the intermediate value.

The capacitor 1| is connected between anode I49 and cathode I5I of thedischarge device 69 through a resistor I53, thus establishing adischarge circuit for the capacitor 1| which exeither cause an increaseor a charge device 15. A mid-tap of potentials between the A capacitorcapacitor through the resistor I53, anode I49, cathode Ill and to theother side of the capacitor 1|. The capacitor 1| is charged by means ofa circuit which extends from end of resistor I55, which is energized bythe rectifier I I, through conductor I51, capacitor 1| adjustableresistor 13 to a selected tap I59 on the resistor I55.

Similarly the capacitor 11 is connected between anode I6| and cathodeI68 of the discharge device 15 through a resistor I55. The capacitor 11is charged by means of a circuit which extends from one end of theresistor I55 through the conductor I51, capacitor 11, adjustableresistor 19, the tap I59 and resistor I55.

One end of the resistor 83 of the bridge network 8| is connected to acontrol electrode I81 01 the discharge device 69. The other end isconnected to a control electrode I59 of the dis- I1I on resistor 83 isconnected by means of conductor I13 to one end of a resistor I15. Theother end of resistor I 15 is connected by means of conductor I11 to theresistor I55. A circuit for: supplying a plurality control electrode I61and the cathode I 5| of the discharge device 69 thus extends from thecontrol electrode I61 through resistor 83, mid-tap I1I, conductor I13,resistor I15, conductor I11, resistor I55, tap I59, adjustable resistor13 to the cathode I5. I. Similarly the control circuit for the .dischardevice 15 extends from the control electrode I69 rough the resistor 83,mid-tap I 1| conductor I 13, re-

sistor I15, conductor I11, resistor I55, tap I59, adjustable resistor 19to the cathode I63.

The resistor I15 is energized from the rectifier 3 through an electricdischarge device I19 which is controlled by the light sensitive means45. When the disc 51 intercepts the light beam from the light source 55to the photo-electric device 53, the discharge device I19 and thus theresistor I15 are energized. When the disc 51 is in such a position thatthe photo-electric device 53 becomes actuated by the light beam passingthrough the slot 59, the discharge device I19 and thus the resistor I15becomes deenergized.

Each pair of electric discharge devices 9| and 63 is connected in a wellknown manner to obtain full-wave rectification. To control the operationof the pair of discharge devices 6| a circuit extends from the controlelectrodes of the pair of devices 6| through conductor I8I, adjustableresistor 13, tap I59, conductor I83, an adjustable source of negativebias I85, an adjustable source of dephased potential I81 to the cathodesof the discharge devices 6|. To control the operation of the pair ofdischarge from the control electrodes of the pair of devices 89 throughconductor I89, adjustable resistor 19,

tap I59, conductor I83, an adjustable source of negative bias I85, anadjustable source of dephased potential I81 to the cathodes of thedischarge devices 63.

As the material 23 advances from the feeding device 2| to the cutter I1,the spot 25 first modifies the illumination on the photo-electric device41, causing the potential of the control electrode 91 relative to thecathode 93 to become more negative and thus decreasing the currentthrough the discharge device 9| below the intermediate value. The bridgenetwork becomes unbalanced in such a manner that the right hand end ofthe resistor 83 becomes negative with respect to the left hand end.Assuming that the spot 25 is devices 63 a circuit extends will interceptthe light beam from the source 55 and, therefore, resistor I15 will beenergized. Because resistors I55 and I15 are energized the controlelectrode I61 does not become sufficiently positive with respect to thecathode |5l to energized discharge device 69. At this time the controlelectrode I69 of discharge device 15 becomes still more negative withrespect to the cathode I63.

Still assuming that the apparatus is in synchronism, the spot 25 willadvance until it is no longer scaned by photo-electric device 41. Thenslot 59 in disc 51'reaches such a position that photoelectric device 53becomes actuated, thus deenergizing the discharge device I19 and,therefore, the resistor I15 becomes deenergized. Both control electrodesI61 and I69 become more positive but because resistor 83 is nowdeenergized and resistor I55 is energized, the control electrodes I61and I69 are not sufliciently positive to energize the discharge devices69 and 15.

The spot advances until it causes photo-electric device 49 to function.During synchronism the photo-electric device 53 will again be dark andresistor I15 energized at this time. The current through the dischargedevice 9| will thus increase above the intermediate value causing thebridge network 8| to become unbalanced in such a manner that the righthand end of the resistor 83 becomes positive with respect to the lefthand end. The control electrode I69 will become more positive, butbecause of the energized resistor I55 and I15. it will not besufiiciently positive to energize the discharge device 15. At this timethe control electrode I61 of discharge device 69 becomes still morenegative.

If the apparatus is out of synchronism and the cutter cuts the materialtoo soon or leads, the spot 25 causes the photo-electric device 41, andthe slot 59 causes the photo-electric device 53 to function so that theresistor I15 is deenergized. Thus the control electrode I61 momentarilybecomes sufficiently more positive and the discharge device 69 isenergized. The capacitor 1| discharges immediately and thus decreasesthe anode to cathode potential so that the discharge device 69 becomesdeenergized. The capacitor 1| is then charged through adjustableresistor 13 as hereinbefore explained. The potential drop across theadjustable resistor 13 due to the charging current thus causes the pairof discharge devices 6| to become energized. The field winding 31 andthe armature of motor 35 are then energized and the motor is operated insuch a direction that the speed of the web material 23 is increased. Themotor 35 continues to operate while the capacitor 1| is being charged.

The time interval between spots 25,, that is the time required for aspot to travel a distance equal to the distance between two succeedingspots, is very short. By adjusting the resistor 13, the time requiredfor charging the capacitor 1| can be made longer than the time intervalbetween spots. As long as the web is out of synchronism with the cutter,the next succeeding spot will cause the capacitor 1| to be dischargedwhile there is still sufficient charging current passing throughresistor 13 to maintain the discharge devices BI in the energizedcondition. Thus the motor 35 continues to operate until the cutter 35operates on the web 23 at the proper time.

For intermittent operation of the motor 35 while tween spots the indicla25 is out of 19 may be adjusted so synchronism, the resistor that thetime interval beis longer than the time required for charging thecapacitor 1|. It will readily be understood that the interval betweenspots need not be equal to the time required for the disc 51 and thusthe slot 59 to rotate one revolution. It is sufllcient that spots bespaced so that the time interval required for suitable operation be somemultiple of the time required for one revolution of the disc 51 orcutter l1.

It will be clear from the above described operation that had the cutterI1 cut the material too late or lagged, the spot 25 would have causedthe photo-electric device 49 to function substantially simultaneouslywith the actuation of photo-electric device 53. Thus the dischargedevice 15 would be energized, which in turn would cause the energizationof the pair of discharge devices 63 and the field winding 39. The motor35 would rotate in the reverse direction, that is, in such a directionas to cause the speed of the web to decrease. The motor 35 wouldcontinue to operate until the web is again in synchronism. Since theseoperations are similar to those hereinabove described, it is believedunnecessary to the understanding of the invention to repeat adescription of these operations.

Should both pairs of discharge devices 6| and 63 become energized at thesame time, a resistor |9I is provided to protect the motor 35 fromexcessive currents.

In the modification shown in Fig. 2, corresponding elements have beengiven the same reference characters and only such elements as are notfound in Fig. 1 are referred to by different reference characters. Thesystem in Fig. 2 diflers primarily from that shown in Fig. 1 in that anelectromagnetic device 20I having an operating coil 203 and a set ofcontacts 205 is utilized in place of the pair of discharge devices 6|and an electromagnetic switch 201 having an operating coil 209 and a setof contacts 2 is utilized in place of the pair of discharge devices 63for controlling the operation of motor 35. The operating coil 203 isconnected in the circuit for charging the capacitor 1|, one end of theoperating coil is connected to the adjustable resistor 13 and the otherend is connected to the junction between the capacitor 1| and thecathode I5I. Similarly, the operating coil 209 is connected between theadjustable resistor 19 and the capacitor 11. The contacts 205 and 2| Iare connected in the circuit of field winding 31 and 39 respectively.

The operation of the system in Fig. 2 is similar to that hereinabovedescribed with reference to Fig, 1 except that after the dischargedevice 69 has functioned the current for recharging the capacitor 1|also energizes the operating coil 203. The electro-magnetic device MI isactuated to close contacts 205, thus energizing the field winding 31 andthe armature of motor 35. The motor may continue to operate, dependingupon the adjustment of resistor 13, until the web material 23 is againin synchronism with the cutter I1.

Similarly, after the discharge device 15 has functioned, the current forrecharging the capacitor 11 also energizes the operating coil 209. Theelectromagnetic device 201 is actuated to close contacts 2| I, thusenergizing the field winding 39 and the armature of motor 35. The motor35 then operates to again bring the web in synchronism with the cutterI1.

In the control systems hereinabove described with reference to Figs. 1and 2, both photoelectric devices 01. and 4| scan the indicia II. Whileone photo-electric device 41 or 0 scans the spot II, the other continuesto act as a compensating device by scanning the web 13. However. it willreadily be understood that only one of the photo-electric devices 41 and49 need be used for scanning the indicia 25 while the other continuouslyscans the web. II. For example, the photo-electric device 41 is sopositioned that it scans the indicia II and the web 23 while thephoto-electric device 48 scans the web in a region that, relativelyspeaking, moves parallel to the indicia 25.

The arm I" is so adjusted on resistor I that the discharge device llconducts an intermediate value of current suiiicient to balance thecurrents in the bridge network 8i so that the voltage across resistor 83is zero when the photo-electric device 01 scans a certain predeterminedportion oi the spot II. When the photo-electric device 41 scans a largerportion 01' the spot 25, the discharge device conducts a current largerthan the intermediate value, thuscausing the right hand end of resistor83 to become more positive than the left hand end. when thephoto-electric device 4'! scans a smaller portion 01' the spot 26 thedischarge device !i conducts a current smaller than the intermediatevalue, thus causing the right hand end of resistor 83 to become morenegative than the left hand end.

I do not wish to be restricted to the specific structural details,arrangement of parts or -circuit connections herein set forth, asvarious other modifications thereof may be eflected without departingfrom the spirit and scope of my invention. I desire, therefore, thatonly such limitations shall be imposed as are indicated in the appendedclaims.

I claim as my invention:

1. In a web controller, in combination, a cutter, a web-feedingmechanism for advancing web material carrying indicia at specifiedpoints longitudinally thereof, speed adjusting means mechanicallyconnected between the said cutter and the said web-feeding means, amotor for operating the said speed adjusting means, a pair ofphoto-electric devices cooperatively associated with the web and theindicia, the said photoelectric devices being interconnected in abalanced network, selective control means including a discharge deviceresponsive to the diflerential effect of the said photo-electricdevices, light-sensitive means cooperatively associated with the cutter,and electronic timing means controlled by the cooperative action of thesaid selective control means and the said light-sensitive means forcontrolling the operation 01' the said motor to adjust the speed on thesaid cutter relative to the said web-feeding mechanism.

2. Apparatus for maintaining the relative position of a strip ofmaterial fed to a machine having an element operating on the stripcomprising, in combination, means for efl'ecting a change in therelative positions of the strip and the said element, a motor connectedto actuate the means for efl'ecting a change in the relative positionsof the strip and the said element, a pair of photo-electric devicesinterconnected in a balanced network and cooperatively associated withthe strip, selective control means including a discharge deviceresponsive to the difl'erential effect of the said photo-electricdevices, lightsensitive means cooperatively associated with the saidelement, electronic timing means controlled by the cooperative action ofthe said selective control means and the said light-sensitive meansi'orselectlvelycontroliing the operation 01' the said motor wherebyafter a departure oi the strip of material from a predetermined relationwith reference to the said element the strip of material is repositionedin proper relapair of photo-electric devices interconnected in abalanced network and cooperatively associated with the strip, selectivecontrol means including a discharge device responsive to thediflerential effect ofthesaid photo-electric devices, electrical timingmeans controlled by the said selective control means for selectivelycontrolling the operation of the said motor alter a departure of thestrip of material from a predetermined relation with reference to thesaid element to reposition the strip of material in proper relation tothe element in one continuous operation of the motor.

4. Apparatus for maintaining the relative position of a strip ofmaterial fed to a machine having an element operating on the stripcompris ing, in combination, means for efiecting a change in therelative positions of the strip and the' said element, a motor connectedto actuate the means for efiecting a change in relative positions of thestrip and the said element, a first light sensitive means cooperativelyassociated with the said strip, a second light sensitive means directlycooperatively associated with the said element, and means controlled bysaid first and second lightsensitive means for selectively controllingthe said motor after a departure of the strip of material from apredetermined relation with reference to the said element.

5. Apparatus for maintaining the relativeposition of a strip of materialfed to a machine having an element operating on the strip comprising, incombination, means for efiecting a change in the relative speed of thestrip and the said element, a motor connected to actuate the means foreffecting a change in relative speed of the strip and the said element,a first light sensitive means cooperatively associated with the saidstrip, a second light sensitive means directly cooperatively associatedwith the said element, and means controlled by said first and secondlightsensitive means for selectively controlling the said motor wherebyafter adeparture of the strip of material from a predetermined relationwith reference to the said element the speed of the.

said strip relative to the said element is adjusted to reposition thestrip in proper relation to the element in one continuous operation ofthe motor.

6. Apparatus for maintaining the relative position of a strip ofmaterial fed to a machine having an element operating on the stripcomprising, in combination, means for effecting a change in the relativepositions of the strip and the said element, a motor connected toactuate-the means for eii'ecting a change in relative positions of thestrip and the said element, a first light sensitive means cooperativelyassociated with the said strip, a second light sensitive means directly00- operatively associated with the said element, and meanssimultaneously controlled by said first and second light-sensitive meansfor selectively controlling the said motor after a departure of thestrip of material from a predetermined relation with reference to thesaid element.

'7. Apparatus for maintaining the relative position of a strip ofmaterial fed to a machine having an element operating on the stripcomprising, in combination, means for effecting a change in the relativespeed of the strip and the said element, a motor connected to actuatethe means for eiIecting a change in relative speed of the strip and thesaid element, a first light sensitive means cooperatively associatedwith the said strip, a second light sensitive means directlycooperatively associated with the said element, and means simultaneouslycontrolled by said first and second light-sensitive means forselectively controlling the said motor whereby after a departure of thestrip of material from a predetermined relation with reference to thesaid element the speed of the said strip relative to the said element isadjusted to reposition the strip in proper relation to the element inone continuous operation of the motor.

8. In a web controller, in combination, a cutter, a web feedingmechanism for advancing web material carrying indicia at specifiedpoints longitudinally thereof, position adjusting means mechanicallyconnected between the saidcutter and the said web-feeding means, a pairof photoelectric devices cooperatively associated with the web and theindicia, the said photo-electric devices being interconnected in abalanced network, selcctive control means including a discharge deviceresponsive to the difierential effect of the said photo-electricdevices, lightsensitive means cooperatively associated with the cutter,and electronic timing means controlled by the cooperative action of thesaid selective control means and the said light-sensitive means forcontrolling the operation of the said position adjusting means to adjustthe position of certain parts of the said cutter relative to certainparts of the said web-feeding mechanism.

9. In a web controller, in combination, a cutter, a web-feedingmechanism for advancing web material carrying indicia at specifiedpoints longitudinally thereof, position adjusting means mechanicallyconnected between the said cutter and the said web-feeding means, amotor for operating the said speed adjusting means, a pair ofphoto-electric devices cooperatively associated with the web and theindicia, the said photoelectric devices being interconnected in abalanced network, selective control means including a discharge deviceresponsive to the differential eifect of the said photo-electricdevices, lightsensitive means cooperatively associated with the cutter,and means controlled by the cooperative action of the said selectivecontrol means and the said light-sensitive means for controlling theoperation of the said motor to adjust the speed of the said cutterrelative to the said web-feeding mechanism.

10. Apparatus for maintaining the relative position of a strip ofmaterial fed to a machine having an element operating on the stripcomprising, in combination, means for effecting a change in the relativepositions of the strip and the said element, a pair of photo-electricdevices interconnected in a balanced network and cooperativelyassociated with the strip, selective control means including a dischargedevice responsive to the diiierential eflect oi the said photo-electricdevices, timing means controlled by the said selective control means forselectively controlling the operation of the said means for eiiecting achange in the relative positions of the strip and the said element aftera departure of the strip of material from a predetermined relation withreference to the said element to reposition the strip of material inproper relation to the element in one continuous operation.

11. Apparatus for maintaining the relative position of a strip ofmaterial fed to a machine having an element operating on the stripcomprising, in combination, means for eflecting a change in the relativespeeds, a pair of photo-electric devices interconnected in a balancednetwork and cooperatively associated with the strip, selective controlmeans responsive to the diflerential eiiect of the said photo-electricdevices, for selectively controlling the operation of the said means foreffecting a change in the relative speeds oi. the strip and the saidelement after a departure of the strip of material from a predeterminedrela-- tion with reference to the said element to reposition the stripof material in proper relation to the element.

12. Apparatus for maintaining the relative position of a strip ofmaterial fed to a machine having an element operating on the stripcomprising, in combination, means for effecting a change in the relativepositions of the strip and the said element, a motor connected toactuate the means for effecting a change in relative positions of thestrip and the said element, a first light sensitive means, comprising afirst and a second light sensitive device, cooperatively associated withthe said strip, a second light sensitive means, comprising a singlethird light sensitive device, directly cooperatively associated with thesaid element, and means controlled by said first and secondlight-sensitive means for selectively controlling the said motor after adeparture of the strip of material from a predetermined relation withreference to the said element.

13. Apparatus for maintaining the relative position of a strip ofmaterial fed to a machine having an element operating on the stripcomprising, in combination, means for effecting a change in the relativepositions of the strip and the said element, a motor connected toactuate the means for effecting a change in relative positions of thestrip and the said element, a first, and a second light sensitive meanscooperatively associated with the said strip, a third light sensitivemeans directly cooperatively associated with the said element, and meanscontrolled by said first, second, and third light-sensitive means forselectively controlling the said motor after a departure of the strip ofmaterial from a predetermined relation with reference to the saidelement.

14. Apparatus for maintaining the relative position of a strip ofmaterial fed to a machine having an element operating on the stripcomprising, in combination, means for eflecting a change in the relativespeed of the strip and the said element, a motor connected to actuatethe means for effecting a change in relative speed of the strip and thesaid element, a first light sensitive means, comprising a first and asecond light sensitive device, cooperatively associated with the saidstrip, a second light-sensitive means, comprising a single thirdlight-sensitive device, directly cooperatively associated with the saidelement, and means controlled by said first and second light-sensitivemeans for selectively controlling the said motor whereby after adeparture oi the strip of material from a predetermined relation withreference to the said element the speed of the said strip relative tothe said element is adjusted to, reposition the strip in proper relationto the element in one continuous operation of the motor.

15. Apparatus for maintaining the relative position of a strip ofmaterial ted to a machine having an element operating on the stripcomprising, in combination, means for eifecting a change in the relativepositions of the strip and the said element, a motor connected toactuate the means for efi'ecting a change in relative positions oi thestrip and the said element, a first light-sensitive means, comprising afirst and a second light sensitive device, cooperatively associated withthe said strip, a second light-sensitive means, comprising a singlethird light sensitive device, directly cooperatively associated with thesaid element, and means simultaneously controlled by said first andsecond light-sensitive means for selectively controlling the said motorafter a departure of the strip of material from a predetermined relationwith reference to the said element.

16. Apparatus for maintaining the relative position 01' a strip ofmaterial fed to a machine having an element operating on the stripcomprising, in combination, means for effecting a change in the relativespeed of the strip and the said element, a motor connected to actuatethe means for effecting a change in relative speed of the strip and thesaid element, a first light sensitive means, comprising a first and asecond light sensitive device, cooperatively associated with the saidstrip, a second light sensitive means, comprising a third lightsensitive device, directly cooperatively associated with the saidelement, and means simultaneously controlled by said first and secondlight-sensitive means for selectively controlling the said motor wherebyafter a departure of the strip of material from a predetermined relationwith reference to the said element the speed of the said strip relativeto the said element is adjusted to re-position the strip in properrelation to the element in one continuous operation of the motor.

FINN H. GULLIKSEN.

